The present invention pertains to a device generally referred to in the art as a tube connector. This device is utilized to connect thin wall conduit, tubes, or the like, such as found in refrigeration apparatus, to high-pressure test equipment for testing of the apparatus before it is put into service. In the pretesting of such equipment on an assembly-line basis or where equipment is already installed, it is necessary to be able to connect the equipment to the testing apparatus quickly and easily. Numerous devices of this general type exist in the prior art, as set forth in the following U.S. Pat. Nos.: 2,819,733, 3,542,076, 3,727,952, 3,738,688, 3,779,587, 3,799,207, 3,868,132, 4,326,407, and 4,540,201.
One problem, however, which has existed in devices of the type illustrated in Racine Patent 3,868,132 is that when the tube is inserted and the handle is rotated to the locked position and the tube is then pressurized, the pressure acting against the side face of the seal urges it away from the face of the piston thereby promulgating a leak path for pressure to escape along the seal face and then between the piston and housing. No prior art device has effectively resolved this problem.